Lead anode for electroplating



Jan. 14, 1958 w. E. BELKE ET AL LEAD ANODE FOR "ELECTROPLATING 2 Sheets-Sheet 1 Filed Feb. 28, 1955 \INVENTORS.

Jan. 14, 1958 w. E. BELKE ET AL 2,820,005 7 LEAD ANODE FOR ELECTROPLATING Filed Feb. 28, 1955 2 Sheets-Sheet 2 .INVENTORS. WM @8366 W ,L 0W.

LEAD ANODE FOR ELECTROPLATING William E. Belke and Harvie J. Johnson, Chicago, Ill., assignors to Belke Manufacturing Co., Chicago, Ill., a corporation of Illinois Application February 28, 1955, Serial No. 490,774

6 Claims. (Cl. 204-286) The present invention relates to anodes for electroplating and methods of making them, and is particularly concerned with improved high density anodes and methods which permit the user to make and replace anodes as they are needed.

One of the objects of the invention is the provision of improved lead anodes for electroplating, which are so constructed that the lead of which the anode is made may be suitably shaped in certain shapes of indeterminate length and kept in stock and cut off for electrodes of any desired length and secured to removable anode hooks by the user of electrodes.

Another object of the invention is the provision of improved lead anodes for electroplating, the construction of which permits the user to buy the lead required and 7 made in certain stock shapes, cut to the desired length, and by means of a simple operation the lead may be so modified that it is ready to be secured to removable anode hooks by means of tools which are readily available in any electroplating plant.

Another object is the provision of an improved anode structure which is adapted to be collapsed or extended to make it narrower or wider, or which may be curved or bent to conform to a circular object, without changing the anode area.

Another object of the invention is the provision of im- .proved lead anodes provided with improved removable supporting means, which also serve as an electrical connector, so that the lead for the anodes may be purchased by the ton in random lengths to be cut by the user and formed into new electrodes by him, using the same connectors over and over again, thereby reducing the cost of the anodes.

Another object of the invention is the provision of improved lead anodes for electroplating, having quickly detachable and quickly attachable connector books, so that the lead for the anodes may be purchased already cut to length, formed and drilled; and the removable anode hooks may be used indefinitely by attaching new lengths of lead anode material to them.

Another object of the invention is the provision of improved methods of making lead anodes for electroplating which methods eliminate the securing of anode hooks to the anode by casting a body of metal about the end of the hook and the end of the anode, and which permits the anode hooks of the present invention to be used over and over again by securing thereto lengths of lead anode material which are quickly attachable.

Another object of the invention is the provision of improved methods of making anodes and improved anode structures, which may be employed at a reduced cost and which reduce the waste of material.

While the present electrode is described in connection with the use of lead or lead alloys, we desire it to be understood that the electrode may be made of various types of metal and alloys, depending on the p it is to be used.

reat" Another object of the invention is the provision of improved lead anodes for electroplating having the following advantages:

(1) Higher efficiency and reduced cost.

(2) Greater plating efficiency due to maximum anode surface area.

(3) More uniform deposit and elimination ofwarping.

(4) High current density and low connector resistance.

(5) High gassing concentration at a multiplicity of corners with increased turbulence and flue action that sweeps away bubbles.

(6) Simple in construction and having a minimum number of parts, the lead being replaceable.

Other objects and advantages of the inventionwill be apparent from the following description and the accompanying drawings, in which similar characters of refer ence indicate similar parts throughout the several views.

Referring to the drawings accompanying the specifications, of which there are two sheets,

Fig. 1 is a view in perspective of an installation, showing a plurality of lead anodes ready for use;

Fig. 2 is a view in perspective of a lead anode constructed according to the invention;

Fig. 3 is a sectional view on a larger scale, taken on the plane of the line 3--3 of Fig. 2, looking in the direction of the arrows;

Fig. 4 is a similar view of a modified form of electrode;

Fig. 5 is a sectional view taken through the securing bolt on the plane of the line 5-5 of Fig. 2;

Fig. 6 is an expanded view in perspective of the parts at the top of the electrode;

Fig. 7 is a fragmentary sectional view taken through the hook at the point of its support on the anode rod, showing the way in which the insulating covering is removed to permit the hook and rod to come into electrical conducting engagement;

Fig. 8 is a fragmentary view in perspective of electrode material clamped in a suitable clamping device to hold corrugations in predetermined shape, while the end is being compacted and drilled for attachment to the hook.

Fig. 9 is a fragmentary view in perspective of an improved end formation for the electrode, in which the corrugations are collapsed more abruptly.

Referring to Fig. 1, 10 indicates an electroplating tank, the top of which supports a rod 11 for carrying anodes. A plurality of anodes 12 of similar construction are hooked over the anode rod 11, so that they hang depending i the electroplating solution in the tank 10.

Fig. 2 is a view in perspective of a lead anode-iconstructed according to the invention, and when we refer to the anode as being made of lead in this specification and claims, we mean an anode of which the major part is lead,

pose for which as such anodes are customarily constructed of an alloy which may be ninety-four percent lead and six percent antimony.

The anode 12 of Fig. 2 includes a body 13, comprising an elongated bar which is preferably extruded in its present form, having a plurality of zigzag formations 14, extending back and forth from one side of the bar to the other, forming a plurality of corrugations, the outer surfaces of which are spaced from each other to expose a maximum amount of external surface to the solution in a minimum amount of space.

These corrugations are preferably of substantially V- shape with rounded apices 15, and all formed on a uniform angle and of a uniform width; but in some embodiments of the invention the angularity, width and shape may be varied. The apices are preferably rounded, permitting Jeasier bending at these apices, and in some embodiments the The lead, which is kept at a suitable tempei'ature and pressure so that it is adapted to be extruded, is extruded through a die having the cross-sectional shape of the corrugated electrode of Fig.3 or Fig. 4.

As the lead emerges from the die it is cooled by water, cold air or other cooling means and it forms a rigid, corrugated electrode bar.

These electrode bars are made in suitable lengths so that they may be kept in stock and sold by the ton to be cut off by the user. They may also be cut off and formed by the vendor of the bars, who may provide the compact end formation on each bar and drill the required hole.

In some embodiments of the invention the deformation of the bar at one end into a compact block may be localized by so quickly impacting the bar with a hammer that inertia causes the rest of the bar to keep its corrugated formation.

In other cases the corrugated bar is clamped in a rigid complementary clamp, such as that shown in Fig. 8, at a point close to the end so that when the end is compressed its corrugations are collapsed into a fiat block without changing the shape of the rest of the bar which is located in the clamp and beyond the clamp.

Thereafter a hole may be drilled or punched in the compact block and the electrode bar is then ready to be attached to a combined connector and supporting hook.

Our method includes the casting or other ways of forming a combined electrode supporting hook and connector which has a V-shaped hook portion provided with a lower knife edge and forming the hook with an inwardly extending shank centered below the apex of the V.

We also prefer to form the hook with a laterally extending ofiset leading to a depending portion, with an enlargement that supports a bolt formed integrally with the hook and extending in the same direction as the electrode rod that is to support the hook.

We prefer to form this head with an enlargement having a thrust surface for engaging the lead electrode block, and the end of the bolt is threaded and provided with a nut which has an enlarged thrust flange to engage the lead block.

The hook is then coated over-all with a layer of plastic insulation which hardens into a solid coating and which is excluded from the bolt and the thrust flanges by covering them with an adhesive tape during the immersion of the hook in the plastic.

During this immersion the nut may be placed on the threaded end of the bolt and driven home to exclude the plastic from the threads of the bolt. The nut is preferably a cap nut which excludes the insulation from the other end of the bolt.

The bolt and the two thrust surfaces of nut and head may be kept bare of plastic by merely placing a spacer on the bolt during the immersion of the hook in the plastic.

The plastic covering the lower V-shaped knife edge of the hook is preferably ground away to expose this knife edge of metal, so that it may effect a low resistance contact with the electrode rod.

When the hook has been completed, it is placed in the aperture of an electrode bar and the bar is clamped by means of the nut, thereby completing the process of forming an electrode assembly.

As often as the lead is used up a new electrode bar is provided and secured on the hook.

Our improved electrode structures are adapted to reduce considerably the cost of providing anodes for electroplating since the connector books may be used over and over again, and the electrode bars may be kept in stock and cut to length as required by the user.

While we have illustrated a preferred embodiment of our invention, many modifications may be made without departing from the spirit of the invention, aadwe do not wish to be limited to the precise details of construction set forth, but desire to avail ourselves of all changes within the scope of the appended claims.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States, is:

1. A lead anode assembly for electroplating compris ing, a connector hook having an upper V-shaped formation for engaging on anode rod and effecting an electrical connection, said hook having a threaded bolt extending laterally from its lower end in a direction similar to the direction of the anode rod, a lead electrode mounted on said bolt and depending therefrom, and a threaded member on the threaded end of said bolt clamping the electrode between said threaded member and a shoulder at the other end of said bolt, the, said electrode comprising a bar of lead alloy material having an aperture in its upper end, and having the rest of its body formed with a multiplicity of folds extending back and forth forming an elongated corrugated electrode, the said corrugations being substantially V-shaped in form with rounded apices, and the corrugations being deformed at the end about said aperture for said bolt until the corrugations are brought into firm engagement with each other.

2. An anode assembly for electroplating processes, comprising a downwardly open V-shaped hook member provided on its under and inner side with surfaces at an angle to each other, forming a pair of converging apices on the inside of the hook, said hook having a downwardly and forwardly extending body terminating at a central angular portion located below the apex of the V hook, said angular portion having a laterally extending offset and a downwardly extending shank integrally attached to a headed member formed with an integral cylindrical body for securement to an anode, said cylindrical body having a threaded end portion for receiving a clamping member for clamping an anode against said headed portion, and an anode carried by said supporting member and comprising a multiplicity of contacting folds of thick sheet material extending back and forth and formed with U bends joining flanges engaging each other, and having a through bore on said cylindrical member.

3. An anode assembly for electroplating processes, comprising a downwardly open V-shaped hook member provided on its under and inner side with surfaces at an angle to each other, forming a pair of converging apices on the inside of the hook, said hook having a downwardly and forwardly extending body terminating at a central angular portion located below the apex of the V hook, said angular portion having a laterally extending offset and a downwardly extending shank integrally attached to a headed member formed with an integral cylindrical body for securement to an anode, said cylindrical body having a threaded end portion for receiving a clamping member for clamping an anode against said headed porion, and an anode carried by said supporting member and comprising a multiplicity of contacting folds of thick sheet material extending back and forth and formed with U bends joining flanges engaging each other, and having a through bore on said cylindrical member, and a nonmetallic internally threaded cap on the threaded end of said cylindrical member and clamping said folds against said headed portion.

4. An anode assembly for electroplating processes, comprising a downwardly open V-shaped hook member provided on its under and inner side with surfaces at an angle to each other, forming a pair of converging apices on the inside of the hook, said hook having a downwardly and forwardly extending body terminating at a central angular portion located below the apex of the V hook, said angular portion having a laterally extending offset and a downwardly extending shank integrally attached to a headed member formed with an integral cylindrical body for securement to an anode, said cylindrical body having a; threaded end portion for receiving a clamping memher for. clamping an anode against said headed portion, and an anode/carried by said supporting member and comprising a multiplicity of contacting folds of thick sheet material extending back and forth and formed with U bends joining flanges engaging each other, and having a through bore on said cylindrical member, the said folds of sheet metal being spread from each other adjacent their through bore and having an elongated portion which is formed with relatively sharp V-shaped corrugations extending from end to end.

An anode assembly for electroplating processes, comprising a downwardly open V-shaped hook member provided onv its under and inner side with surfaces at an angle to each other, forming a pair of converging apices on the inside of the hook, said hook having a downwardity and forwardly extending body terminating at a central angular portion located below the apex of the V hook, said angular portion having a laterally extending offset and a downwardly extending shank integrally attached to a headed member formed with an integral cylindrical body for securefnent to an anode, said cylindrical body having a threaded end portion for receiving a clamping member for clamping an anode against said headed portion, and an anode carried by said supporting member and comprising a multiplicity of contacting folds of thick sheet material extending back and forth and formed with U bends joining flanges engaging each other, and having a through bore on said cylindrical member, the said folds of sheet metal being spread from each other adjacent their through hole and having an elongated portion which is formed with relatively sharp V-sliaped corrugations extending from end to end,- and a nonmetallic internally threaded cap on the threaded end of said cylindrical member and clamping said folds against said headed portion.

6. An electrode for use in an electroplating anode-assembly, comprising a thick sheet metal member having a multiplicity of contacting folds, extending back and forth, and formed withbends joining flanges engaging each other, said flanges having registering cylindrical through bores'for. receiving a cylindrical supporting member, said bends diverging from each other in a tapered bellows portion of said electrode adjacent said" through bores, and being integrally joined to an elongated portion of maximum exposed area, having elongated openings between folds on the sides o posite to the bends.

References Cited in the file of this patent UNITED STATES PATENTS 477,220 Naef June 21, 1892 639,811 Haas s a r Dec. 26, 1899 1,517,633 Junkers r Dec. 2, 1924 1,650,518 Humphris Nov. 2 2', 1927 2,274,056 Gieger .ta Feb. 24, 1942 2,3315320' Hartzell- Oct; 12-, 1943 2,723,230 Godsey -.w NOV. 8, 1955 FOREIGN PATENTS 627,484 Great Britain ha assed- Aug. 10, 1949 126,931 Sweden au e. and Sept. 6, 1949 986,289 France s -s n Mar. 21, 1 951 675,799 Great. Britain July 16, 1952 481,591 Italy June 3, 1953 GTHER- REFERENCES Tlrews: Anodes,"" Fiat Report No; 882, July 25, 1946, pp. 5, 6, '7. 

1. A LEAD ANODE ASSEMBLY FOR ELECTROPLATING COMPRISING, A CONNECTOR HOOK HAVING AN UPPER V-SHAPED FORMATION FOR ENGAGING ON ANODE ROD AND EFFCTING AN ELECTRICAL CONNECTION, SAID HOOK HAVING A THREADED BOLT EXTENDING LATERALLY FROM ITS LOWER END IN A DIRECTION SIMILAR TO THE DIRECTION OF THE ANODE ROD, A LEAD ELECTRODE MOUNTED ON SAID BOLT AND DEPENDING THEREFROM, AND A THREADED MEMBER ON THE THREADED END OF SAID BOLT CLAMPING THE ELECTRODE BETWEEN SAID THREADED MEMBER AND A SHOULDER AT THE OTHER END OF SAID BOLT, THE SAID ELECTRODE COMPRISING A BAR OF LEAD ALLOY MATERIAL HAVING AN APERTURE IN ITS UPPER END, AND HAVING THE REST OF ITS BODY FORMED WITH A MULTIPLICITY OF FOLDCS EXTENDING BACK AND FORTH FORMING AN ELONGATED CORRUGATED ELECTRODE, THE SAID CORRUGATIONS BEING SUBSTANTIALLY V-SHAPED IN FORM WITH ROUNDED APICES, AND THE CORRUGATIONS BEING DEFORMED AT THE END ABOUT SAID APERTURE FOR SAID BOLT UNTIL THE CORRUGATIONS ARE BROUGHT INTO FIRM ENGAGEMENT WITH EACH OTHER. 